Fkm is a fluororubber material. Fkm is the abbreviation of fluororubber. Fluorine rubber refers to a synthetic polymer elastomer with fluorine atoms in its main chain or side chain carbon atoms. The introduction of fluorine atoms gives rubber excellent heat resistance, oxidation resistance, oil resistance, corrosion resistance and atmospheric aging resistance. Widely used in aerospace, aviation, automobile, petroleum, household appliances and other fields, it is an irreplaceable key material for national defense cutting-edge industries. Since 1943, polyolefin fluororubber, nitroso fluororubber, tetrapropyl fluororubber, phosphazene fluororubber and perfluoroether rubber have been developed successively.